thejim42 Posted January 22, 2014 Posted January 22, 2014 I just got my 88 all put together this past summer. 4.0 with a 5 speed 2wd. The motor was rebuilt by my uncle when in 2002 and wrapped it up and set it in the bed for the last 10 or so years. The engine has about 1200 miles on it and i ran a compression check and the engine has low compression. every cylinder is around 70 psi and when i put oil in the cylinders, compression jumped to 95-100 psi. I'm thinking it is a ring issue. Since the engine sat for so long before it was finally run and broke in, and all the cylinders are so close together with their compression could the rings just be stuck? I really don't feel like taking the damn truck apart again so any advice would be greatly appreciated.
jimoshel Posted January 22, 2014 Posted January 22, 2014 I wouldn't worry about it. They just might not be seated and a couple miles under the belt just might do it. If the rings were stuck a couple drops of oil wouldn't raise the compression that much. Ive seen engines that had been sitting for 20 years when first fired up would darn near empty the pan they smoked so bad. Run them awhile and they cleared up.
cruiser54 Posted January 22, 2014 Posted January 22, 2014 Have you run the engine yet? Was the compression test done on a warm engine or just when you unwrapped it? Either way, I'm with Jim. Run it.
thejim42 Posted January 22, 2014 Author Posted January 22, 2014 I've put 1200 miles on it and just did the compression test yesterday and it was warm when I did the test
HOrnbrod Posted January 22, 2014 Posted January 22, 2014 I've put 1200 miles on it and just did the compression test yesterday and it was warm when I did the test How does the engine run? Assume not well since you did a compression test?
thejim42 Posted January 22, 2014 Author Posted January 22, 2014 I've put 1200 miles on it and just did the compression test yesterday and it was warm when I did the test
thejim42 Posted January 22, 2014 Author Posted January 22, 2014 It runs okay...it has a slight miss and a high idle
thejim42 Posted January 22, 2014 Author Posted January 22, 2014 I'm not sure why it keeps reposting my one post
HOrnbrod Posted January 22, 2014 Posted January 22, 2014 It runs okay...it has a slight miss and a high idle Your high idle is most likely being caused by a vacuum leak (cracked and/or unconnected vacuum line). So, if you fixed the high idle by correcting the vacuum leak, it would run okay and well enough to drive with no worries?
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now